The contribution deals with quality evaluation of timber based on the modulus of elasticity, modulus of rupture and density of spruce wood. The relationships between MOE and density, MOR and density, MOE and MOR are analysed. All experimental results and calculated relationships are compared to the standard results and relationships. Effect of density to the tested mechanical properties (MOE and MOR) is significant and with increasing of density the values of both mechanical properties increased too. The relationship between MOE and MOR is very closed and direct proportion.